Commit 90a3ccb0 authored Dec 27, 2015 by Michael S. Tsirkin

sh: define __smp_xxx, fix smp_store_mb for !SMP



sh variant of smp_store_mb() calls xchg() on !SMP which is stronger than
implied by both the name and the documentation.

define __smp_store_mb instead: code in asm-generic/barrier.h
will then define smp_store_mb correctly depending on
CONFIG_SMP.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>

parent 82b44496

arch/sh/include/asm/barrier.h

+2 −1

Original line number	Diff line number	Diff line
		@@ -32,7 +32,8 @@
		#define ctrl_barrier() __asm__ __volatile__ ("nop;nop;nop;nop;nop;nop;nop;nop")
		#endif

		#define smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0)
		#define __smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0)
		#define smp_store_mb(var, value) __smp_store_mb(var, value)

		#include <asm-generic/barrier.h>

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